1. Field of the Invention
The present invention relates to a work transfer device which is employed in a multi-process press machine combined with a plurality of metal mold sets for sequentially transferring the work from one process step to another.
2. Description of Related Art
A generally employed work transfer device has been disclosed in Patent Publication No. 2504382, for example. The disclosed device is structured such that the feed bar to which the work suction fitting (holding fitting) is attached is moved two dimensionally, that is, longitudinal direction and lateral direction on the vertical plane including the work transfer direction such that the work is sequentially transferred from one process step to another. The aforementioned two dimensional movement of the feed bar is performed by two cams. Meanwhile Japanese Patent Application Laid-Open No. 10-328766 discloses the transfer press carrying device structured to move the work suction fitting (holding fitting) three-dimensionally in X-axis,Y-axis, and Z-axis directions such that the work transfer may be performed more smoothly at higher rates.
The transfer press carrying device in which the work is three-dimensionally transferred as disclosed in Japanese Patent Application Laid-Open No. 10-328766 is provided with a plurality of servo motors, a position detection sensor, an encoder, and a controller that execute predetermined computing operations based on data detected by various detection units as described above such that the work suction fitting (holding fitting) is moved to a predetermined position based on the computed result. Accordingly, the resultant structure of the device for the work transfer becomes complicated and large in size.